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Multi-dimensional multiplexing optical secret sharing framework with cascaded liquid crystal holograms 被引量:3
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作者 Keyao Li Yiming Wang +6 位作者 Dapu Pi Baoli Li Haitao Luan Xinyuan Fang Peng Chen Yanqing Lu Min Gu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期28-35,共8页
Secret sharing is a promising technology for information encryption by splitting the secret information into different shares.However,the traditional scheme suffers from information leakage in decryption process since... Secret sharing is a promising technology for information encryption by splitting the secret information into different shares.However,the traditional scheme suffers from information leakage in decryption process since the amount of available information channels is limited.Herein,we propose and demonstrate an optical secret sharing framework based on the multi-dimensional multiplexing liquid crystal(LC)holograms.The LC holograms are used as spatially separated shares to carry secret images.The polarization of the incident light and the distance between different shares are served as secret keys,which can significantly improve the information security and capacity.Besides,the decryption condition is also restricted by the applied external voltage due to the variant diffraction efficiency,which further increases the information security.In implementation,an artificial neural network(ANN)model is developed to carefully design the phase distribution of each LC hologram.With the advantage of high security,high capacity and simple configuration,our optical secret sharing framework has great potentials in optical encryption and dynamic holographic display. 展开更多
关键词 holographic encryption optical secret sharing cascaded liquid crystal hologram multi-dimensional multiplexing
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Neurocircuit regeneration by extracellular matrix reprogramming
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作者 Shengzhang Su Ian N.Levasseur Kimberly M.Alonge 《Neural Regeneration Research》 SCIE CAS 2025年第8期2300-2301,共2页
The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functio... The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases. 展开更多
关键词 matrix PROGRAMMING
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Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration
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作者 Ronglin Han Lanxin Luo +4 位作者 Caiyan Wei Yaru Qiao Jiming Xie Xianchao Pan Juan Xing 《Neural Regeneration Research》 SCIE CAS 2025年第5期1364-1376,共13页
Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to p... Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering. 展开更多
关键词 ALGINATE axon growth BIOMATERIALS extracellular matrix neural repair neurons NEUROREGENERATION POLYACRYLAMIDE POLYDIMETHYLSILOXANE stiffness
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THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX
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作者 HE Fang-guo 《数学杂志》 2025年第1期1-12,共12页
This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh ... This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic hypergraphs.The spectral radius of the graph is generalized. 展开更多
关键词 spectral radius uniform hypergraph Signless Laplasian matrix
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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Immunohistochemical expression of matrix metalloproteinase-9 and 13 in oral squamous cell carcinoma and their role in predicting lymph node metastasis
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作者 Bhari Sharanesha Manjunatha Keshav T Handge +2 位作者 Vandana Sandeep Shah Yasser Eid Al-Thobaiti Deepak Gowda Sadashivappa Pateel 《World Journal of Methodology》 2025年第2期108-116,共9页
BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors... BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remo-deling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.The authors wish to thank Jadhav KB for his valuable opinion during the preparation of the manuscript. 展开更多
关键词 matrix metalloproteinases Oral squamous cell carcinoma Tumor staging IMMUNOHISTOCHEMISTRY INVASION Lymph node metastasis TNM stage
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The Study on College English Writing Based on Multi-dimensional Feed-back Mode
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作者 骆敏 徐敏娜 《海外英语》 2020年第12期273-274,共2页
The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the stud... The study constructed a multi-dimensional feedback mode integrating teacher feedback, peer feedback and network feedback, and applied it in the teaching of College English Writing. After 16 weeks of teaching, the students in the multi-dimen-sional feedback class had significantly better overall writing scores than those in the teacher-feedback class. In terms of individual scores, multi-dimensional feedback played a better role in improving vocabulary and grammar than the class using teacher feed-back. However, there were no significant differences in the responses of writing tasks, coherence and cohesion. The study showed that most students were satisfied with the mode, believing that it was helpful to relieve writing anxiety, stimulate writing interest and improve their writing level. 展开更多
关键词 College English Writing multi-dimensional feedback MODE
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Structural Engineering of Hierarchical Aerogels Comprised of Multi-dimensional Gradient Carbon Nanoarchitectures for Highly Efficient Microwave Absorption 被引量:19
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作者 Yongpeng Zhao Xueqing Zuo +11 位作者 Yuan Guo Hui Huang Hao Zhang Ting Wang Ningxuan Wen Huan Chen Tianze Cong Javid Muhammad Xuan Yang Xinnan Wang Zeng Fan Lujun Pan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第9期344-363,共20页
Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing imped... Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing impedance mismatch are significant challenges.Herein,the delicate“3D helix-2D sheet-1D fiber-0D dot”hierarchical aerogels have been successfully synthesized,for the first time,by sequential processes of hydrothermal self-assembly and in-situ chemical vapor deposition method.Particularly,the graphene sheets are uniformly intercalated by 3D helical carbon nanocoils,which give a feasible solution to the mentioned problem and endows the as-obtained aerogel with abundant porous structures and better dielectric properties.Moreover,by adjusting the content of 0D core-shell structured particles and the parameters for growth of the 1D carbon nanofibers,tunable electromagnetic properties and excellent impedance matching are achieved,which plays a vital role in the microwave absorption performance.As expected,the optimized aerogels harvest excellent performance,including broad effective bandwidth and strong reflection loss at low filling ratio and thin thickness.This work gives valuable guidance and inspiration for the design of hierarchical materials comprised of dimensional gradient structures,which holds great application potential for electromagnetic wave attenuation. 展开更多
关键词 Hierarchical aerogels multi-dimensional gradient Carbon nanocoils Microwave absorption
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Seismic fragility analysis of highway bridges considering multi-dimensional performance limit state 被引量:16
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作者 Wang, Qi'ang Wu, Ziyan Liu, Shukui 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期185-193,共9页
Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility... Fragility analysis for highway bridges has become increasingly important in the risk assessment of highway transportation networks exposed to seismic hazards. This study introduces a methodology to calculate fragility that considers multi-dimensional performance limit state parameters and makes a first attempt to develop fragility curves for a multi-span continuous (MSC) concrete girder bridge considering two performance limit state parameters: column ductility and transverse deformation in the abutments. The main purpose of this paper is to show that the performance limit states, which are compared with the seismic response parameters in the calculation of fragility, should be properly modeled as randomly interdependent variables instead of deterministic quantities. The sensitivity of fragility curves is also investigated when the dependency between the limit states is different. The results indicate that the proposed method can be used to describe the vulnerable behavior of bridges which are sensitive to multiple response parameters and that the fragility information generated by this method will be more reliable and likely to be implemented into transportation network loss estimation. 展开更多
关键词 highway bridge seismic hazard multi-dimensional performance limit state fragility curves sensitivity
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NEW STRUCTURES FOR NON-SELFSIMILAR SOLUTIONS OF MULTI-DIMENSIONAL CONSERVATION LAWS 被引量:4
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作者 杨小舟 魏涛 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1182-1202,共21页
In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. Th... In this article, we get non-selfsimilar elementary waves of the conservation laws in another kind of view, which is different from the usual self-similar transformation. The solution has different global structure. This article is divided into three parts. The first part is introduction. In the second part, we discuss non-selfsimilar elementary waves and their interactions of a class of twodimensional conservation laws. In this case, we consider the case that the initial discontinuity is parabola with u+ 〉 0, while explicit non-selfsirnilar rarefaction wave can be obtained. In the second part, we consider the solution structure of case u+ 〈 0. The new solution structures are obtained by the interactions between different elementary waves, and will continue to interact with other states. Global solutions would be very different from the situation of one dimension. 展开更多
关键词 non-selfsimilar shock wave rarefaction wave ENVELOPE multi-dimensional conservation laws
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Heavy oil component characterization with multi-dimensional unilateral NMR 被引量:4
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作者 Liu Huabing Xiao Lizhi +6 位作者 Guo Baoxin Zhang Zongfu Zong Fangrong Deng Feng Yu Huijun V.Anferov S.Anferova 《Petroleum Science》 SCIE CAS CSCD 2013年第3期402-407,共6页
Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficien... Heavy oil is a complicated mixture and a potential resource and has attracted much attention since the end of last century. It is important to characterize the composition of heavy oil to enhance its recovery efficiency. A designed unilateral Nuclear Magnetic Resonance (NMR) sensor with a Larmor frequency of 20 MHz and a well-defined constant gradient of 23.25 T/m was employed to acquire three- dimensional (3D) data for three heavy oil samples. The highly-constant gradient is advantageous for diffusion coefficient measurement of heavy oil. A fast data-implementation procedure including specially designed 3D pulse sequence and Inversion Laplace Transform (ILT) algorithm was adopted to process the data and extract 3D T1-D-T2 probability function. It indicates that NMR relaxometry and diffusometry are useful to characterize the components of heavy oil samples. NMR results were compared with independent measurements of fractionation and gas chromatography analysis. 展开更多
关键词 Heavy oil multi-dimensional NMR unilateral sensor
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Structure and cavitation erosion behavior of HVOF sprayed multi-dimensional WC-10Co4Cr coating 被引量:10
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作者 Xiang DING Xu-dong CHENG +3 位作者 Xiang YU Chao LI Cheng-qing YUAN Zhang-xiong DING 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第3期487-494,共8页
A new kind of multi-dimensional WC-10Co4Cr coating which is composed of nano,submicron,micron WC grains and CoCr alloy,was developed by high velocity oxy-fuel(HVOF)spraying.Porosity,microhardness,fracture toughness an... A new kind of multi-dimensional WC-10Co4Cr coating which is composed of nano,submicron,micron WC grains and CoCr alloy,was developed by high velocity oxy-fuel(HVOF)spraying.Porosity,microhardness,fracture toughness and cavitation erosion resistance of the multi-dimensional coating were investigated in comparison with the bimodal and nanostructured WC?10Co4Cr coatings.Moreover,the cavitation erosion behavior and mechanism of the multi-dimensional coating were explored.Results show that HVOF sprayed multi-dimensional WC-10Co4Cr coating possesses low porosity(≤0.32%)and high fracture toughness without obvious nano WC decarburization during spraying.Furthermore,it is discovered that the multi-dimensional WC-10Co4Cr coating exhibits the best cavitation erosion resistance which is enhanced by approximately 28%and 34%,respectively,compared with the nanostructured and bimodal coatings in fresh water.The superior cavitation resistance of multi-dimensional WC-10Co4Cr coating may originate from the unique micro?nano structure and excellent properties,which can effectively obstruct the formation and propagation of cavitation erosion cracks. 展开更多
关键词 WC-10Co4Cr cavitation erosion multi-dimensional coating high velocity oxy-fuel(HVOF)spraying MICROSTRUCTURE
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Analysis of multi-dimensional SAR for determining the thickness of thin sea ice in the Bohai Sea 被引量:5
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作者 张晰 张杰 +1 位作者 孟俊敏 苏腾飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第3期681-698,共18页
Flat thin ice (<30 cm thick) is a common ice type in the Bohai Sea, China. Ice thickness detection is important to offshore exploration and marine transport in winter. Synthetic aperture radar (SAR) can be used to ... Flat thin ice (<30 cm thick) is a common ice type in the Bohai Sea, China. Ice thickness detection is important to offshore exploration and marine transport in winter. Synthetic aperture radar (SAR) can be used to acquire sea ice data in all weather conditions, and it is a useful tool for monitoring sea ice conditions. In this paper, we combine a multi-layered sea ice electromagnetic (EM) scattering model with a sea ice thermodynamic model to assess the determination of the thickness of flat thin ice in the Bohai Sea using SAR at different frequencies, polarization, and incidence angles. Our modeling studies suggest that co-polarization backscattering coefficients and the co-polarized ratio can be used to retrieve the thickness of flat thin ice from C- and X-band SAR, while the co-polarized correlation coefficient can be used to retrieve flat thin ice thickness from L-, C-, and X-band SAR. Importantly, small or moderate incidence angles should be chosen to avoid the effect of speckle noise. 展开更多
关键词 multi-dimensional SAR sea ice in the Bohai Sea flat thin ice thickness retrieval
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Low-Temperature Growing Anatase TiO2/SnO2 Multi-dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells 被引量:7
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作者 Linsheng Huang Xiaowen Zhou +7 位作者 Rui Xue Pengfei Xu Siliang Wang Chao Xu Wei Zeng Yi Xiong Hongqian Sang Dong Liang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第3期199-217,共19页
A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Base... A multi-dimensional conductive heterojunction structure,composited by TiO2,SnO2,and Ti3C2TX MXene,is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells.Based on an oxygen vacancy scramble effect,the zero-dimensional anatase TiO2 quantum dots,surrounding on two-dimensional conductive Ti3C2TX sheets,are in situ rooted on three-dimensional SnO2 nanoparticles,constructing nanoscale TiO2/SnO2 heterojunctions.The fabrication is implemented in a controlled lowtemperature anneal method in air and then in N2 atmospheres.With the optimal MXene content,the optical property,the crystallinity of perovskite layer,and internal interfaces are all facilitated,contributing more amount of carrier with effective and rapid transferring in device.The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%,yet that of counterpart is just 16.83%.In addition,it can also maintain almost 85%of its initial performance for more than 45 days in 30–40%humidity air;comparatively,the counterpart declines to just below 75%of its initial performance. 展开更多
关键词 In situ fabrication multi-dimensional heterojunction Oxygen vacancy scramble effect Electron transport layer Perovskite solar cells
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ON MULTI-DIMENSIONAL SONIC-SUBSONIC FLOW 被引量:2
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作者 黄飞敏 王天怡 王勇 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2131-2140,共10页
In this paper, a compensated compactness framework is established for sonicsubsonic approximate solutions to the n-dimensional (n ≥ 2) Euler equations for steady irrotational flow that may contain stagnation points... In this paper, a compensated compactness framework is established for sonicsubsonic approximate solutions to the n-dimensional (n ≥ 2) Euler equations for steady irrotational flow that may contain stagnation points. This compactness framework holds provided that the approximate solutions are uniformly bounded and satisfy Hloc^-1(Ω) compactness conditions. As illustration, we show the existence of sonic-subsonic weak solution to n-dimensional (n ≥ 2) Euler equations for steady irrotational flow past obstacles or through an infinitely long nozzle. This is the first result concerning the sonic-subsonic limit for n-dimension (n ≥ 3). 展开更多
关键词 multi-dimension sonic-subsonic flow steady irrotational flow compensated compactness
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Practical security of continuous-variable quantum key distribution under finite-dimensional effect of multi-dimensional reconciliation 被引量:2
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作者 Yingming Zhou Xue-Qin Jiang +3 位作者 Weiqi Liu Tao Wang Peng Huang Guihua Zeng 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期101-107,共7页
The well-known multi-dimensional reconciliation is an effective method used in the continuous-variable quantum key distribution in the long-distance and the low signal-to-noise-ratio scenarios.The virtual channel empl... The well-known multi-dimensional reconciliation is an effective method used in the continuous-variable quantum key distribution in the long-distance and the low signal-to-noise-ratio scenarios.The virtual channel employed to exchange data is generally established by using a finite-dimensional rotation in the reconciliation procedure.In this paper,we found that the finite dimension of the multi-dimensional reconciliation inevitably leads to the mismatch of the signal-to-noise-ratio between the quantum channel and the virtual channel,which may be called the finite-dimension effect.Such an effect results in an overestimation on the secret key rate,and subsequently induces vital practical security loopholes. 展开更多
关键词 multi-dimensional reconciliation finite-dimensional effect continuous-variable quantum key distribution
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Finding Main Causes of Elevator Accidents via Multi-Dimensional Association Rule in Edge Computing Environment 被引量:2
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作者 Hongman Wang Mengqi Zeng +1 位作者 Zijie Xiong Fangchun Yang 《China Communications》 SCIE CSCD 2017年第11期39-47,共9页
In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and impl... In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and implementing a method by combining classical Apriori algorithm with the model, digging out frequent items of elevator accident data to explore the main reasons for the occurrence of elevator accidents. In addition, a collaborative edge model of elevator accidents is set to achieve data sharing, making it possible to check the detail of each cause to confirm the causes of elevator accidents. Lastly the association rules are applied to find the law of elevator Accidents. 展开更多
关键词 elevator group accidents APRIORI multi-dimensional association rules data cube edge computing
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A MICROPAYMENT SCHEME BASED ON WEIGHTED MULTI-DIMENSIONAL HASH CHAIN 被引量:2
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作者 Liu Yining Hu Lei Liu Heguo 《Journal of Electronics(China)》 2006年第5期791-794,共4页
Hash chain and its generalization—Multi-Dimensional Hash Chain (MDHC) have been widely used in the design of micropayment due to its simplicity and efficiency. In this letter, a more efficient variant of MDHC, called... Hash chain and its generalization—Multi-Dimensional Hash Chain (MDHC) have been widely used in the design of micropayment due to its simplicity and efficiency. In this letter, a more efficient variant of MDHC, called WMDHC, which endows in the structure of MDHC a weight value for each hash value through a well-defined mapping, is proposed. The average hash operation number of WMDHC is log(2 m / t ),which is better than log( m )of MDHC when the parameter t is typically suggested as t = 7. 展开更多
关键词 Micropayment multi-dimensional flash Chain (MDHC) Hamming weight
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Multi-dimensional scattering properties diagnosis system of scale aircraft model in an anechoic chamber 被引量:1
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作者 Chufeng Hu Zhou Zhou +1 位作者 Nanjing Li Kun Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期588-595,共8页
Aiming at the concept of "diagnosis", a simple and effective broadband radar cross section (RCS) measurement system is constructed, and some multi-dimensional scattering properties diagnosis techniques are present... Aiming at the concept of "diagnosis", a simple and effective broadband radar cross section (RCS) measurement system is constructed, and some multi-dimensional scattering properties diagnosis techniques are presented based on the system. Firstly, a stepped-frequency signal is employed to achieve high range resolution, combining with a variety of signal processing tech- niques. Secondly, cross-range resolution is gained with a rotating table, and the high-resolution two-dimensional (2-D) imaging of the scale model is obtained by the microwave imaging theory. Finally, two receiving antennas with a small distance in altitude are used, and the three-dimensional (3-D) height distribution of scattering points on the scale model is extracted from the phase of images. Some typical bodies and a scale aircraft model are diagnosed in an anechoic chamber. The experimental results show that, after scaling with a metal sphere, the accurate one- dimensional (l-D) RCS pattern of the model is obtained, and it has a large dynamic range. When the bandwidth of the transmitting signal is 4 GHz, the resolution of the 2-D image can reach to 0.037 5 m. The 3-D height distribution of scattering points is given by interferometric measurement. This paper provides a feasible way to obtain high-precision scattering properties parameters of the scale aircraft model in a conventional rectangular anechoic chamber. 展开更多
关键词 DIAGNOSIS STEPPED-FREQUENCY multi-dimension anechoic chamber.
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A branch-and-bound algorithm for multi-dimensional quadratic 0-1 knapsack problems 被引量:2
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作者 孙娟 盛红波 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期233-236,共4页
In this paper, a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied. The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding ... In this paper, a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied. The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding feasible solutions. The Lagrangian relaxations were solved with the maximum-flow algorithm and the Lagrangian bounds was determined with the outer approximation method. Computational results show the efficiency of the proposed method for multi-dimensional quadratic 0-1 knapsack problems. 展开更多
关键词 multi-dimensional quadratic 0-1 knapsack problem branch-and-bound method Lagrangian relaxation outer approximation surrogate constraint.
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